The present invention relates to health foodstuff containing Dunaliella algae and a process for the production thereof. More particularly, the present invention relates to solid foodstuff comprising various kinds of active components which are present in Dunaliella algae, especially .beta.-carotene and a process for producing the same without destroying said active components.
It has been well known that Chlorella algae, which belong to the species of unicellular Chlorophyceae, are used for the purposes of preparing daily food or health food in the form of a tablet. It has also been known that Dunaliella algae produce a lot of .beta.-carotene therein when the algae are grown in a culture fluid containing a high concentration of saline and a small amount of nitrogen under strong natural light and other appropriate conditions. It is public knowledge in the art that natural .beta.-carotene derived from Dunaliella algae is utilized in the form of a suspension in vegetable oil as natural coloring agents for food, cosmetics, feed and the like or as material regulating vital functions such as a nourishing diet supplement. However, no practical proposal had been made concerning the method of fully utilizing Dunaliella algae per se for health-oriented food without destroying the .beta.-carotene contained therein.
Dunaliella algae contain proteins, lipids, mineral substances such as iron, sugars, vitamins and a variety of other physiologically active ingredients. Among these nutrients, .beta.-carotene, one of the provitamin A group of compounds, is liable to oxygen because it contains conjugated double bond chains. This presents a serious problem in the manufacture of health food containing Dunaliella algae. It has therefore been strongly desired to develop a method by which the algae can be processed without destroying natural .beta.-carotene, and the product preserved in a stable state.
The present inventor actively investigated possible solutions for the aforementioned problems. As a result of such investigation, he has completed the present invention.